An article transport device described above transports articles between (a) an operator's transfer location at which an operator performs transfer work, including supplying articles to be transported to an article transport device and receiving articles which have been transported by the article transport device, and (b) a non-operator's transfer location at which an automated device performs transfer work which includes supplying articles to be transported to an article transport device and receiving articles which have been transported by the article transport device.
In the article transport device described above, an area above the reciprocating movable body is covered with a cover to, among other things, prevent spreading of dust generated in the drive portion of the reciprocating movable body or of vapor of lubricating oil with which the drive portion is lubricated, and to prevent unwanted objects from entering into the travel path in which the reciprocating movable body travels in both directions. A slit is formed in this cover body along the travel path. And a connecting portion, which connects an article support and the reciprocating movable body, extends upwardly from the reciprocating movable body and vertically through the slit formed in the cover body. And the article support for supporting an article, connected to the reciprocating movable body by a connecting portion, is moved along the direction of the travel path by the movements of the reciprocating movable body in forward and backward directions along the travel path and below the cover body.
An example of a conventional article transport device of a type described above includes one in which the slit is formed such that the connecting portion remains in contact with the cover body when the reciprocating movable body moves along the travel path (see for example, Patent Document 1). In the article transport device of Patent Document 1, the portion which forms the slit in the cover body has edges that are elastically urged, over the total length of the slit, in the directions that tend to close the slit. The width of the slit is widened depending on the position of the connecting portion by virtue of the fact that the connecting portion, which moves with the movement of the reciprocating movable body, spreads apart the corresponding portion's of the two edges. With regard to the article transport device of Patent Document 1, it is stated that it is desirable for the ends of both edges to be formed with hard resin material with small coefficient of friction and with good anti-wear characteristics in order to reduce contact resistance between the connecting portion and the cover body when the connecting portion moves and spreads both edges apart as it moves.